TUKWILA, Wash. – Clint Dempsey is on the verge of making his return to Major League Soccer after more than six months away due to a heart issue.

Dempsey is expected to be in the lineup when the Seattle Sounders open the season on Saturday at Houston. Seattle general manager Garth Lagerwey and coach Brian Schmetzer indicated Tuesday that Dempsey will be in the lineup against the Dynamo, although how much he plays will be watched closely.

“I would think there is a pretty high probability of that,” Schmetzer said as Seattle returned home after participating in the Carolina Challenge Cup in Charleston, South Carolina, to close out its preseason.

Dempsey has been a full participant through most of Seattle’s preseason, watching his minutes increase during the Sounders’ four exhibition games. He started slowly, but Dempsey capped his preseason by playing 80 minutes in the final exhibition last Saturday, a 1-0 loss to Columbus.

Even though Dempsey has been medically cleared, Lagerwey said Seattle will be very cautious moving forward so as to not overwork Dempsey early on. Seattle is doing that with a number of its veteran players.

“To state the obvious, we’re still six months removed from the last time he played 90 minutes in a match. So that is still going to be a work in progress,” Lagerwey said. “We are not going to push anybody back quickly at this point. It’s far more important to us how we look later in the season than in March.”

Dempsey, who turns 34 on March 9, has not played in an MLS game since Aug. 21, when he had two goals in a 3-1 win over Portland. The team announced he had an irregular heartbeat shortly after and Dempsey missed the rest of the season.

Dempsey said earlier this month that the symptoms that eventually led him to being diagnosed with an irregular heartbeat first surfaced last February but that it wasn’t until late summer that it became serious enough to affect his ability to play.

“It was a heart issue. It’s something that’s difficult to kind of explain,” Dempsey said on Feb. 14. “But at the same time I’m not feeling those things anymore and I’m happy to be back playing.”